The American Heritage® Dictionary of the English Language, 4th Edition
n. Any of various grouses of the genus Lagopus, inhabiting arctic, subarctic, and alpine regions of the Northern Hemisphere and having feathered legs and feet and plumage that is brown or gray in summer and white in winter.
n. Any of three species of small grouse in the genus Lagopus found in subarctic tundra areas of North America and Eurasia.
the GNU version of the Collaborative International Dictionary of English
n. Any grouse of the genus Lagopus, of which numerous species are known. The feet are completely feathered. Most of the species are brown in summer, but turn white, or nearly white, in winter.
The Century Dictionary and Cyclopedia
n. A bird of the family Tetraonidæ and genus Lagopus, having feathered feet.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. large Arctic and subarctic grouse with feathered feet and usually white winter plumage
Word Usage
"We were far into the Brooks Range foothills now, at 3,100 feet, and perhaps the altitude would pay bonus points in ptarmigan."